Volume 37, Issue 1, Pages 74-84 (July 2012) The Antimicrobial Protein REG3A Regulates Keratinocyte Proliferation and Differentiation after Skin Injury  Yuping Lai, Dongqing Li, Changwei Li, Beda Muehleisen, Katherine A. Radek, Hyun Jeong Park, Ziwei Jiang, Zhiheng Li, Hu Lei, Yanchun Quan, Tian Zhang, Yelin Wu, Paul Kotol, Shin Morizane, Tissa R. Hata, Keiji Iwatsuki, Ce Tang, Richard L. Gallo  Immunity  Volume 37, Issue 1, Pages 74-84 (July 2012) DOI: 10.1016/j.immuni.2012.04.010 Copyright © 2012 Elsevier Inc. Terms and Conditions

Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 1 Psoriasis Patients and Imiquimod-Induced Psoriatic Mouse Skin Have High Abundance of REG3A or RegIIIγ in Lesional Skin (A) Quantification of REG3A mRNA expression of skin from normal, basal cell carcinomas, atopic dermatitis, and psoriasis patients. N.D., not detectable. (B) Immunofluorescent staining of skin in normal and psoriasis patients by REG3A antibody. Scale bars represent 200 μm. (C) Immunofluorescent staining of normal and imiquimod-induced psoriatic mouse skin by RegIIIγ antibody. Scale bars represent 100 μm. (D and E) Quantification of IL-17a and RegIIIγ mRNA expression of skin from normal and imiquimod-induced psoriatic mouse ears or backs. ∗p < 0.05, ∗∗p < 0.01; n.s., no significance. p values were determined by one-way or two-way ANOVA. Data are the means ± SEM. See also Figure S1. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 2 Skin Injury Increases Epidermal RegIIIγ Expression (A) The expression of RegIIIγ mRNA of 2 mm skin surrounding the wound edge 3 days after aseptic injury. (B and C) Quantification of RegIIIγ and RegIIIα expression of skin treated as in (A). (D) Immunoblot of RegIIIγ in skin extracts from mouse wound edges. (E) Immunofluorescent staining of skin in wild-type mouse treated as in (A) by RegIIIγ antibody. The scale bars represent 50 μm. ∗∗∗p < 0.001. p values were determined by two-tailed t tests. Data are the means ± SEM of six mice for each. See also Figure S2. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 3 IL-17 Activates IL-17RA to Induce REG3A or RegIIIγ Expression in Primary Keratinocytes and Skin Adjacent to Wound Edge (A) Quantification of REG3A mRNA expression in undifferentiated NHEKs stimulated by different cytokines. (B) The expression of REG3A mRNA induced by the indicated doses of IL-17A. (C) Immunofluorescent staining of undifferentiated NHEKs treated with 1,000 ng ml−1 IL-17A by REG3A antibody. Scale bars represent 100 μm. (D) The expression of REG3A after IL-17RA was silenced. (E) RegIIIγ expression in undifferentiated primary murine keratinocytes stimulated by the supernatant of skin wound homogenate pretreated with control IgG or IL-17a-neutralizing antibody. (F) RegIIIγ expression in mouse skin wounds after IL-17a was neutralized by IL-17a-neutralizing antibody. (G) Immunofluorescent staining of skin in wild-type mouse treated as in (F) by RegIIIγ antibody. The scale bars represent 100 μm. (H) RegIIIγ expression in skin wounds of Il17−/− and wild-type mice. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001. p values were analyzed by two-tailed t test or one-way ANOVA. Data are the means ± SEM of n = 3. See also Figure S3. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 4 REG3A Increases Keratinocyte Proliferation via the Inhibition of Differentiation Gene Expression (A) REG3A induced undifferentiated NHEK proliferation analyzed by MTT. (B) Undifferentiated keratinocytes in S phase by flow cytometry. The percentage of cells in S phase increased by REG3A was calculated by the amount of cells in S phase at each indicated concentration divided by the amount of total cells. (C) Quantification of differentiated gene expression in undifferentiated NHEKs. (D) Cell number after NHEKs were treated with 0.1 nM REG3A and/or 1.6 mM CaCl2. (E) Differentiated keratinocytes back into S phase induced by REG3A. (F and G) CaCl2-induced loricrin (LOR) and filaggrin (FLG) expression in the presence or absence of REG3A. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001; n.s., no significance. p values were analyzed by one-way or two-way ANOVA. Data are the means ± SEM of n = 3. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 5 REG3A or RegIIIγ Promotes Wound Reepithelialization and Psoriatic Hyperproliferation (A) Percentage of scratch wound healing of undifferentiated NHEKs. (B) Percentage of scratch wound healing of differentiated NHEKs. (C) Identical fields treated as in (B) at 0 and 24 hr scratch. The yellow dotted line represents the area of the scratch at t = 0 hr. The green dotted line represents the area of the scratch at t = 24 hr. (D) RegIIIγ promoted wound healing in vivo. (E) Wound healing at day 3 after IL-17a or RegIIIγ blockage. (F) Imiquimod-induced ear thickness with or without RegIIIγ blockage. (G) Imiquimod-induced epidermal hyperproliferation with or without RegIIIγ blockage. Scale bars represent 100 μm. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001; n.s., no significance. p values were determined by one-way or two-way ANOVA. Data are represented as the mean ± SEM of n = 3–6. See also Figure S4. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 6 EXTL3 Is Required for REG3A Activation in Keratinocytes (A) REG3A bound to EXTL3 in human keratinocytes. (B) Loricrin expression induced by REG3A after EXTL3 was silenced. (C) Immunofluorescent staining of skin by loricrin antibody after EXTL3 blockage. The scale bars represent 100 μm. (D) Loricrin expression in mouse wounded skin treated as in (C). (E and F) Cell proliferation and wound healing induced by REG3A after EXTL3 was silenced. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001; n.s., no significance. p values were determined by one-way ANOVA. Data are means ± SEM of n = 3. See also Figure S5. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions

Figure 7 REG3A or RegIIIγ Activates PI3K-AKT Signaling Pathway to Regulate Keratinocyte Differentiation (A and B) Loricrin expression of NHEKs treated with REG3A and/or inhibitors wortmannin and Ly294002. (C) The proliferation of NHEKs treated as in (A). (D) Loricrin in wounds of mice treated with RegIIIγ or wortmannin. (E) Wound healing of mice treated with wortmannin. (F) Phosphorylation of AKT after NHEKs were treated REG3A and/or EXTL3 shRNA. (G) Phosphorylation of AKT of NHEKs treated with REG3A and/or wortmannin. ∗p < 0.05, ∗∗p < 0.01, ∗∗∗p < 0.001; n.s., no significance. p values were determined by one-way ANOVA or two-way ANOVA. Data are the means ± SEM of n = 3. Immunity 2012 37, 74-84DOI: (10.1016/j.immuni.2012.04.010) Copyright © 2012 Elsevier Inc. Terms and Conditions